package exp5;

import java.net.*;

import java.io.*;

import java.security.*;

import javax.crypto.*;

import javax.crypto.spec.*;

import java.security.spec.*;

import javax.crypto.interfaces.*;

import java.security.interfaces.*;

import java.math.*;

public class Client {

    public static void main(String srgs[]) throws Exception{

        try {

            KeyGenerator kg=KeyGenerator.getInstance("DESede");

            kg.init(168);

            SecretKey k=kg.generateKey( );

            byte[] ptext2=k.getEncoded();

            //String kstr=parseByte2HexStr(kb);

            //创建连接特定服务器的指定端口的Socket对象

            Socket socket = new Socket("222.28.131.90",2530);

            //获得从服务器端来的网络输入流

            BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));

            //获得从客户端向服务器端输出数据的网络输出流

            PrintWriter out=new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())),true);

            //创建键盘输入流，以便客户端从键盘上输入信息

            BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));



            FileInputStream f3=new FileInputStream("Skey_RSA_pub.dat");

            ObjectInputStream b2=new ObjectInputStream(f3);

            RSAPublicKey pbk=(RSAPublicKey)b2.readObject( );

            BigInteger e=pbk.getPublicExponent();

            BigInteger n=pbk.getModulus();

            BigInteger m=new BigInteger(ptext2);

            BigInteger c=m.modPow(e,n);

            String cs=c.toString( );

            out.println(cs);  //通过网络传送到服务器

            System.out.print("输入发送信息：");

            String s=stdin.readLine(); //从键盘读入待发送的数据

            Cipher cp=Cipher.getInstance("DESede");

            cp.init(Cipher.ENCRYPT_MODE, k);

            byte ptext[]=s.getBytes("UTF8");

            byte ctext[]=cp.doFinal(ptext);

            String str=parseByte2HexStr(ctext);

            out.println(str);  //通过网络传送到服务器

            String x=s;

            MessageDigest m2=MessageDigest.getInstance("MD5");

            m2.update(x.getBytes( ));

            byte a[ ]=m2.digest( );

            String result="";

            for (int i=0; i<a.length; i++){

                result+=Integer.toHexString((0x000000ff & a[i]) |

                        0xffffff00).substring(6);

            }

            System.out.println(result);

            out.println(result);

            str=in.readLine();//从网络输入流读取结果

            System.out.println( "服务器反馈为："+str); //输出服务器返回的结果

        }

        catch (Exception e) {

            System.out.println(e);

        }

        finally{

        }



    }

    public static String parseByte2HexStr(byte buf[]) {

        StringBuffer sb = new StringBuffer();

        for (int i = 0; i < buf.length; i++) {

            String hex = Integer.toHexString(buf[i] & 0xFF);

            if (hex.length() == 1) {

                hex = '0' + hex;

            }

            sb.append(hex.toUpperCase());

        }

        return sb.toString();

    }

    public static byte[] parseHexStr2Byte(String hexStr) {

        if (hexStr.length() < 1)

            return null;

        byte[] result = new byte[hexStr.length()/2];

        for (int i = 0;i< hexStr.length()/2; i++) {

            int high = Integer.parseInt(hexStr.substring(i*2, i*2+1), 16);

            int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16);

            result[i] = (byte) (high * 16 + low);

        }

        return result;

    }

}